1. Technical Field
The present invention relates to coded modulation, and more particularly, to multidimensional coded modulation based on D-dimensional optimum signal constellation design (OSCD).
2. Description of the Related Art
In recent years, there has been a strong impetus for Dense Wavelength Division Multiplexing (DWDM) networks to upgrade from 10 Gb/s per channel to 40/100 Gb/s per channel. Optical transmissions at 100 Gb/s Ethernet data rate has been standardized by ITU-T and IEEE forums. Such transmission rate demand has pushed optical communication systems to a 100 Gb/s Ethernet (100 GbE) standard, with 400 GbE and 1 Tb/s Ethernet (1 TbE) under consideration. While there are technologies that may potentially be used to deliver optical TbE, there remains a number of practical implementation costs and complexity challenges. For example, polarization division multiplexed (PDM) quadrature amplitude modulation (QAM) requires huge QAM constellations to reach Tb/s-range with commercially available symbol rates. Moreover, the terabit optical Ethernet will be affected not only by limited bandwidth of information-infrastructure, but also by its energy consumption.